Source/modules/accessibility/AXListBox.cpp

/*
 * Copyright (C) 2008 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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 */

#include "config.h"
#include "modules/accessibility/AXListBox.h"

#include "core/html/HTMLOptionElement.h"
#include "core/html/HTMLSelectElement.h"
#include "core/layout/LayoutListBox.h"
#include "modules/accessibility/AXListBoxOption.h"
#include "modules/accessibility/AXObjectCacheImpl.h"

namespace blink {

using namespace HTMLNames;

AXListBox::AXListBox(LayoutObject* layoutObject, AXObjectCacheImpl& axObjectCache)
    : AXLayoutObject(layoutObject, axObjectCache)
    , m_activeIndex(-1)
{
    activeIndexChanged();
}

AXListBox::~AXListBox()
{
}

AXListBox* AXListBox::create(LayoutObject* layoutObject, AXObjectCacheImpl& axObjectCache)
{
    return new AXListBox(layoutObject, axObjectCache);
}

AccessibilityRole AXListBox::determineAccessibilityRole()
{
    if ((m_ariaRole = determineAriaRoleAttribute()) != UnknownRole)
        return m_ariaRole;

    return ListBoxRole;
}

AXObject* AXListBox::activeDescendant() const
{
    if (!isHTMLSelectElement(node()))
        return nullptr;

    HTMLSelectElement* select = toHTMLSelectElement(node());
    int activeIndex = select->activeSelectionEndListIndex();
    if (activeIndex >= 0 && activeIndex < static_cast<int>(select->length())) {
        HTMLOptionElement* option = select->item(m_activeIndex);
        return axObjectCache().get(option);
    }

    return nullptr;
}

void AXListBox::activeIndexChanged()
{
    if (!isHTMLSelectElement(node()))
        return;

    HTMLSelectElement* select = toHTMLSelectElement(node());
    int activeIndex = select->activeSelectionEndListIndex();
    if (activeIndex == m_activeIndex)
        return;

    m_activeIndex = activeIndex;
    if (!select->focused())
        return;

    if (m_activeIndex >= 0 && m_activeIndex < static_cast<int>(select->length())) {
        HTMLOptionElement* option = select->item(m_activeIndex);
        axObjectCache().postNotification(option, AXObjectCacheImpl::AXFocusedUIElementChanged);
    } else {
        axObjectCache().postNotification(this, AXObjectCacheImpl::AXFocusedUIElementChanged);
    }
}

} // namespace blink